1. Field of the Invention
The invention relates to an optical module and, in particular, to a compact WDM (Wavelength Division Multiplexing) optical module.
2. Description of the Related Art
In recent years, optical modules are demanded to be a wavelength-division multiplexing type. For example, as a transmitter optical sub-assembly (TOSA) used in an optical module to couple optical signals with different wavelengths emitted from plural light sources and to multiplex the wavelengths, a TOSA in which four CAN packages for housing LDs (laser diode) are arranged in a line so as to face the same direction is known (see JP-A-2007-279507 and JP-A-2008-203427).
Meanwhile, in recent years, the optical modules such as optical transceiver are required to be further downsized. There is a need for a compact optical transceiver meeting, e.g., “QSFP+ (Quad Small Form-factor Pluggable Plus)” which is a transceiver standard for optical fiber supporting 40 to 100 GbE connection, and especially a WDM compact optical transceiver is demanded.